In the Mexican food industry, tortillas, chips, and the like, are commonly formed by sheeting a mass of dough, or masa, into a sheet between a pair of counterrotating sheeter rollers, stripping the dough from the back roller (e.g. with a wire) so that it adheres only to the front roller, and then cutting a pattern from the sheet by rotating a so-called cutter roller against the surface of the front roller.
The patterned sheet is then stripped from the front roller (e.g. with a wire), with the product pieces falling down onto a conveyor belt, and with the surrounding web of “rework” masa, if any, returning to the hopper above the two sheeter rollers to be recombined with fresh masa.
A typical dough sheeter and its cutter roller are disclosed in U.S. Pat. No. 6,530,771 entitled “Rotary Cutter Handling System”, which patent is assigned to the assignee of the present invention and hereby incorporated by reference as if fully set forth herein. A typical cutter roller is also depicted in U.S. Design Pat. No. Des. 391,125 without its stainless steel shaft, the entire disclosure if which is hereby incorporated by reference as if fully set forth herein. This particular design patent depicts a cutter roller that cuts a fish-shaped product pattern into the dough sheet, but more conventional cutter rollers produce triangular chips or round tortillas.
The cutter roller usually has a stainless steel shaft pressed through its length. Conventionally, as shown in FIGS. 1-3, the cutter roller has been supported between two spaced arms 20 (only one is shown), the stainless steel shaft of the cutter rotating with metal-to-metal contact within a brass bushing 30 that fits into a U-shaped end 21 of each lift arm 20.
Some cutter rollers have had their cutting portions made from brass, but they are relatively expensive to manufacturer. More recently, conventional cutter rollers have often been made from plastics like UHMW, a plastic that is relatively soft and that wears quickly, or DELRON®, a plastic that is relatively hard and brittle that chips and also wears quickly. In either case, because the walls of the pattern formed in the UHMW or DELRON® cutter tend to wear against the surface of the sheeter roller, the cutter roller has a short life span that can be as low as only 1-3 months.
There remains a need therefore for a cutter roller with an improved bearing system and that is inexpensive to manufacture and has a long life span.